3.9 diff - anyone tried one?
#1
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3.9 diff - anyone tried one?
I've noticed a few people have mentioned changing their 3.6 CWP for a 3.9 CWP on a 7.5" diff. Man on here done the swap and if so what did you like/dislike about the change?
Also, for those still on the standard speedo cable drive, did you bother having it recalibrated etc and if so where did you get it done?
Also, is it possible to buy the 3.9CWP new still?
Cheers for any experiences
Also, for those still on the standard speedo cable drive, did you bother having it recalibrated etc and if so where did you get it done?
Also, is it possible to buy the 3.9CWP new still?
Cheers for any experiences
#2
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I put a 3.9 on mine because I'm using 18s and it just didn't feel right it would either wheelspin or bog down when launching it and In gear it would spin up too much.
#3
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I was trying to work out if it would be a worthwhile change when rebuilding the diff.
On 205/50x15 tyres the speeds seem to come out roughly ( assuming 6500rpm in Gear ) at :-
1st 41 ( 38 )
2nd 63 ( 59 )
3rd 92 ( 85 )
4th 122 ( 114 )
5th 152 ( 142 )
At motorway speeds it looks roughly like it'd be doing 5mph less for the same revs - seem small differences on paper but was interested to hear of your real world experience
Cheers
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will be using a 4.1/4.2 mysel but that will be for 0/100 more off a b/road thing not top speed.you have too ask yoursell when you going too be using 100mph+ really?? apart from draging and motor way's/fast track's
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Cheers for replying Dan.
I was trying to work out if it would be a worthwhile change when rebuilding the diff.
On 205/50x15 tyres the speeds seem to come out roughly ( assuming 6500rpm in Gear ) at :-
1st 41 ( 38 )
2nd 63 ( 59 )
3rd 92 ( 85 )
4th 122 ( 114 )
5th 152 ( 142 )
At motorway speeds it looks roughly like it'd be doing 5mph less for the same revs - seem small differences on paper but was interested to hear of your real world experience
Cheers
I was trying to work out if it would be a worthwhile change when rebuilding the diff.
On 205/50x15 tyres the speeds seem to come out roughly ( assuming 6500rpm in Gear ) at :-
1st 41 ( 38 )
2nd 63 ( 59 )
3rd 92 ( 85 )
4th 122 ( 114 )
5th 152 ( 142 )
At motorway speeds it looks roughly like it'd be doing 5mph less for the same revs - seem small differences on paper but was interested to hear of your real world experience
Cheers
Here's a video of mine with the 3.6cwp (utterly shit time!!) you can hear it come on boost and try to spin
Check out this video on YouTube:<br/><br/>
And another (again shit )
Check out this video on YouTube:<br/><br/>
#13
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I stopped bothering to run it because it was so frustrating all that waiting and pushing and getting that!! And it was the same on the road in the end I would just big revs and drop the clutch hence getting the option to put the 3.9 in it
The diff is fine, I think I might have fixed the problem and will get some better times next year.
#14
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Not so bothered about losing 10mph off top speed as long as motorway speeds aren't too noisy
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